One of the ways of protecting an object from a projectile is equipping that object with an armour. These armours vary in shape and size to fit the object to be protected. A number of materials e.g., metals, synthetic fibres, and ceramics have been used in constructing the armours. The use of ceramics in constructing armours has gained popularity because of some useful properties of ceramics. Ceramics are inorganic compounds with a crystalline or glassy structure. While being rigid, ceramics are low in weight in comparison with steel; are resistant to heat, abrasion, and compression; and have high chemical stability. Two most common shapes in which ceramics have been used in making armours are as pellets/beads and plates/tiles, each having its own advantages and disadvantages.
U.S. Pat. No. 6,203,908 granted to Cohen discloses an armour panel having an outer layer of steel, a layer of plurality of high density ceramic bodies bonded together, and an inner layer of high-strength anti-ballistic fibres e.g., KEVLAR™.
U.S. Pat. No. 5,847,308 granted to Singh et al. discloses a passive roof armour system comprising of a stack of ceramic tiles and glass layers.
The U.S. Pat. No. 6,135,006 granted to Strasser et al. discloses a multi-layer composite armour with alternating hard and ductile layers formed of fibre-reinforced ceramic matrix composite.
Presently, there are two widely used designs of ceramic components in making armours. The first design, known as the MEXAS design in the prior art comprises a plurality of square planar ceramic tiles. The tiles have a typical size of 1″×1″, 2″×2″, or 4″×4″. The second design known as the LIBA design in the prior art comprises a plurality of ceramic pellets in a rubber matrix. Both designs are aimed at defeating a projectile.
These designs protect an object from a projectile impacting at a low angle. However, the thickness of the tiles in the MEXAS design has to be varied depending upon the level of threat and the angle of the impacting projectile. This increases the weight of the ceramic component and subsequently of the armour. These ceramic components are useful for protecting an object from a low level of threat only and are not suitable for protecting an object from projectiles posing a high level of threat, e.g., the threat posed by a Rocket Propelled Grenade (RPG). Furthermore, an armour assembled by joining a plurality of individual tiles is vulnerable to any level of threat at joints.
Various ceramic systems exist. One example is U.S. Pat. No. 5,326,606 to Labock. Labock teaches a bulletproof panel with a ceramic layer surrounded by a polycarbonate layer. Labock specifies that the polycarbonate layer is used to aid in stopping the projectile and needs to be at least three millimeters thick in the front and six millimeters in the rear. Labock therefore teaches a panel that may be used to stop bullets which can be mounted to a vehicle. The thickness of the polycarbonate layer is similar to that of bulletproof glass and provides several disadvantages. If the ceramic central plate is not flat, a polycarbonate layer that includes a thickness of at least three millimeters will not conform to the ceramic plate. Further, the weight of the polycarbonate front and rear layers add substantially to the armour system.
Therefore, there is a need for producing improved ceramic components, ceramic component systems, and ceramic armour systems that are not only capable of defeating the projectile but are also capable of deflecting the projectile upon impact. There is also a need for reducing the weight of the ceramic components used in the armour systems. There is also a need for improved armour systems capable of deflecting and defeating projectiles posing various levels of threats. There is also a need for providing deflecting and defeating capabilities at the joint points of ceramic components. There is also a need for improved close multi-hit capability, reduced damaged area including little or no radial cracking, reduced back face deformation, and reduced shock and trauma to the object. There is also a need for reducing detection of infrared signature of an object. There is also a need for scattering radar signals by the object.